Quote:
Originally Posted by bns99121
I just bought a 2006 z4 3.0si with the MKIV nav system software version 4-1/70 using the 2006 map DVD. The navigation position is changing but it is usually 50 to 100 miles off from my current position. I took it to my local BMW dealer and they said that the Nav system was fine and that I just needed to buy the 2009 map DVD. I don't mind buying it if it will work but it seems that the DVD is not the problem. Why would the DVD cause this? Next chance I get I will check the GPS Almanac, GPS PDOP value, Signal Strength, and Wheel pulses. Any ideas and any help will be greatly appreciated. By the the car is still under warranty.
Thank You,
Neil
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A DVD map CANNOT cause position errors of that magnitude!
If they did, BMW would have recalled all the maps and replaced them !!
First step: update software to current version. You have 4-1/70. Current ist 4-1/100. Always fixes a few bugs :-) Dealers won't upgrade unless you demand it. But you can do it yourself easily.
2nd step: check GPS status in theService Menu. Look at PDOP values - good positions have PDOP of <5. Look at satellite S/N values. You should see 3 or 4 satellites with S/N between 10 and 15 (higher is better). You should have 6 or 7 satellites being received at any one time. If you see all of satellites with S/N under 5, suspect that the antenna is weak / failing. Make sure of course that the antenna is not covered :-)
3rd step: check dead-reckoning signalling. Does the Direction show Backwards when in reverse, and forwards in all other gears? (req ign to be on). Do speed pulses vary with vehicle speed and show -ve in reverse? Does the gyro show 2500 +/-100 when sitting still, and less when turning left, more when turning right?
4th step: only now suspect map errors - but these are rare and certainly not 100 miles out!! If anything a map error might be less than 1/2 mile out.